The present invention provides an alkali-free glass having a high strain point, a low viscosity and low devitrification, which is easily subjected to float molding and fusion molding. The glass herein has a strain point of 725° C. or higher, an average thermal expansion coefficient at 50 to 300° C. of 30×10−7 to 40×10−7/° C., a temperature T2 at which a glass viscosity becomes 102 dPa·s of 1,710° C. or lower, a temperature T4 at which a glass viscosity becomes 104 dPa·s of 1,330° C. or lower, a glass surface devitrification temperature (Tc) of 1,330° C. or lower, and a glass internal devitrification temperature (Td) of 1,330° C. or lower.
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January 3, 2012
April 30, 2013
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